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Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. FOREWORD The U.S. Geological(More)
The goal of this study was to document if lakes in National Parks in Washington have exceeded critical levels of nitrogen (N) deposition, as observed in other Western States. We measured atmospheric N deposition, lake water quality, and sediment diatoms at our study lakes. Water chemistry showed that our study lakes were ultra-oligotrophic with ammonia and(More)
An investigation was performed to quantify the experience of contour curvature formed under sensory discrepancy inspection conditions. N = 80 male and female undergraduates were used. Experimental Ss finger-tracked a horizontal straight edge while viewing limb movements through a curve inducing lens. Control Ss inspected the edge unimodally, either through(More)
Pesticide mixtures are common in streams with agricultural or urban influence in the watershed. The Pesticide Toxicity Index (PTI) is a screening tool to assess potential aquatic toxicity of complex pesticide mixtures by combining measures of pesticide exposure and acute toxicity in an additive toxic-unit model. The PTI is determined separately for fish,(More)
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